They've already said that they will when the new Mac Pro comes out... I'll find a source for you

Edit, source: https://daringfireball.net/2017/04/the_mac_pro_lives

I think they will... esp with the so-so reviews of the LG... it means there is a market. They will probably wait until their suppliers can produce them at a lower cost and then bring it back. The other key too is getting enough of the 5K laptops out there that can drive it... they need a certain amount of "potential" purchasers to make it worthwhile.

This is just an external display placeholder. It shows the same image for my Dell.

Hope not to be quite honest, spend resources fixing the Mac Pro not just making yet another overpriced screen that sits and gathers dust as technology moves on.

Just buy yourself a nice Dell one and face facts Apple doesn't care about Pro users. Unless you're a "Pro" iPad user

Here is screenshot on mine:

Here's how both Cinema and Thunderbolt look when connected to a MBP with High Sierra

I think it was always like that ;)